The Venlo greenhouse, with Continuous Vents is the evolution of Venlo with alternating vents. Idroterm Serre developed Venlo system with double continuous venting, in order to respond to a demand for greenhouses with high ventilation on the Italian and Mediterranean market. This roof system generates up to 62,5% ventilation, the structures are designed and calculated according to: UNI EN 13031-1:2004, Greenhouses: Design And Construction.